550 



BULLETIN OF THE BUREAU OF FISHERIES 



and sixth rows above and below they become faint, and their distribution is often 

 discontinuous. There are none on the belly or head and only a few on the back. 

 There is usually only one pearl present on each scale, except on the lateral line, 

 where there are sometimes two. In shape the pearls are rounded, showing faintly a 

 narrow longitudinal thickening, are situated in the center and occupy one-third to 

 one-fourth of the exposed scaJe surface on the rows bordering the lateral line. They 

 diminish gradually in size dorsad and ventrad. On the lateral line they are Jess than 

 one-fourth as large as on the adjacent rows and are situated laterad and slightly 

 caudad to the pore. 



VARIATIONS 



Racial variations. — Specimens are available for comparison from Alpena, Mich., 

 and from the Duck Islands across the lake, but the two groups appear little different 

 in their systematic characters. 



Size variations. — The same changes with growth outlined for Lake Michigan 

 specimens seem to obtain in Lake Huron, namely, that small specimens have a larger 

 head and eye, longer paired fins, and less body depth. The figures for specimens 

 under 30 centimeters in length and for those of greater length are compared below 

 for most of these characters: 



L/H: 



Large fish, (4.8) 4.9-5.2 (5.3). 

 Small fish, (4.5) 4.7-5.1 (5.3). 



H/E: 



Large fish, 4.4-4.9. 



Small fish, (3.7) 4-4.3 (4.5). 



Pv/P: 



Large fish, (1.8) 1.9-2.1 (2.3). 

 Small fish, (1.5) 1.7-2 (2.2). 

 Av/V: 



Large fish, 2.1-2.3. 



Small fish, (1.9) 2-2.3 (2.4). 



Individuals apparently show parr marks in their juvenile stages, which, to judge 

 from the two collected specimens under 20 centimeters in length, are not different 

 from those described for small specimens in Lake Michigan. 



None of the collected specimens less than 23 centimeters long are sexually 

 mature, and none over 25 centimeters are immature. 



The maximum size reported for the Jake is about 4 pounds. 



GEOGRAPHICAL DISTRIBUTION 



As in Lake Michigan, schools of pilot are to be found in suitable localities all 

 along the shores of Lake Huron. Likewise the species is not sought much in Lake 

 Huron, and therefore the same limitations exist to the securing of data on the occur- 

 rence and habits of the species. 



On the Canadian shore the pilot seldom is caught for market, but it does occur 

 at other localities in addition to those from which I have collected it, namely, at 

 Tobermory and Providence Bay, according to the statements of Kenneth McLeod 

 and John Purvis. There are other Canadian ports, no doubt, from which it could 

 be caught. On the American shore it is taken not uncommonly, particularly in the 

 fall. It is found in some numbers along the shore from St. Martins Bay f<§ 

 Hammonds Bay, from which area a few are taken to market, both at St. Ignace and 

 Cheboygan. From Hammonds Bay to Middle Island there are said to be none, 

 although in some parts of this area, at least, they have been sought. The Schmekel 



